Cushioned sliding center sill construction



Dec. 14, 1965 w. H. PETERSON CUSHIONED SLIDING CENTER SILL CONSTRUCTION 6 Sheets-Sheet 1 Filed Jan. 2, 1962 INVENTOR. WILUAM H. PETERSON Y w mdwm W FL L-P Dec. 14, 1965 w, PETERSON 3,223,051

CUSHIONED SLIDING CENTER SILL CONSTRUCTION Filed Jan. 2, 1962 s Sheets-Sheet 2 4, 1965 w. H. PETERSON CUSHIONED SLIDING CENTER SILL CONSTRUCTION 6 Sheets-Sheet 3 Filed Jan. 2, 1962 INVENTOR. W\L\ \AM H. PETERSON Dec. 14, 1965 w. H. PETERSON CUSHIONED SLIDING CENTER SILL CONSTRUCTION Filed Jan. 2, 1962 6 Sheets-Sheet 4 N Mv/AS m 1 L F- H w p H L H. w w/flip m W? liiz Dec. 14, 1965 w, PETERSON 3,223,051

CUSHIONED SLIDING CENTER SILL CONSTRUCTION United States Patent 3,223,051 CUSEHONED SLIDING CENTER SILL CONSTRUCTION William H. Peterson, Homewoo'd, 11]., assignor to Pullman Incorporated, Chicago, Ill., a corporation of Delaware Filed Jan. 2, 1962, Ser. No. 163,797 17 Claims. (Cl. 105-454) The present invention relates to railway vehicles and, more particularly, to a new and improved cushioning arrangement for railway vehicle of the cushion underframe type.

Heretofore, cushion underframe vehicles have in general included a sliding center sill mounted for movement longitudinally of the car body in a stationary center sill that is fixed to the underside of the car body. A cushioning device is interposed between the sliding center sill and the car body so as to cushion impacts, either in draft or buff, applied at the couplers, so as to protect lading from damage.

Conventionally, sliding sills of cushion underframe cars have been constructed of a column-like, rigid, unitary, and continuous structure supporting the couplers on each of the respective ends. The couplers are operatively associated in the usual manner with draft gear, which, in cushion underframe constructions, are intended primarily for the purpose of preventing damage to the sliding sill car structure by sufficiently cushioning longitudinal impacts applied at the couplers to reduce the stresses imparted into the sill by such impacts. Railway draft gear, however, is limited in its travel, i.e., about 3 inches, so that the gear is limited in the amount of cushioning it can provide. While efforts have been made to increase draft gear cushioning effectiveness by increasing the energy-absorbing capacity of same with special devices, the cushioning increase achieved has been so limited that up to the present time heavy impact shocks are still imparted to the sliding center sill, tending to cause damage thereto.

Efforts have been made to overcome damage to the sliding center sill by increasing the strength of the structural members forming the column-like unit, thus using more material and adding weight. The success of such efforts is quite limited, however, since by increasing strength, the rigidity is likewise increased with attendant higher stresses and thus only minor improvements are achieved.

It is a principal object of the present invention to provide a sliding center sill or draft and bufiing column construction for the cushion underframe type of railway vehicle which is constructed and arranged so that the cushion device that is interposed between the sliding sill and the car body may be employed to protect the sliding center sill from damage.

It is another object to provide a railway vehicle cushion underframe structure having a sliding sill and an energy-absorbing cushioning means disposed between the vehicle and the sliding sill wherein the sill is extensible and contractible to predetermined positions upon impacts being applied to the sliding sill in draft and buff, respectively, and wherein the cushioning means is operative during the movement of the sill to the predetermined extended or contracted positions to protect the sill itself against such draft and buff impacts.

It is still another object to provide a railway vehicle cushion underframe structure having a sliding sill and an energy-absorbing cushioning means of a selective travel disposed between the sliding sill and the vehicle body primarily for the purpose of reducing lading damage wherein the sliding sill is extensible and contractible to predetermined positions upon impact in draft and buff, respectively, and is arranged to be movable relative to the vehicle body in said predetermined extended and contracted positions and wherein the cushioning means is operative to protect both the lading and the sill during movement of the sill to its contracted position after which sill movement with respect to the vehicle continues to provide further cushioning protection for the lading.

The problem of damage to cushion underframe sliding center sills is of particular significance in railway cars employing cushion underframes of the type in which the center line of the coupler is offset upwardly with respect to the neutral axis of the longitudinally extending center portion of the car. In this type of car, the load-carrying floor is offset downwardly with respect to the coupler level (which is fixed by government regulation) so the sliding sill is similarly contoured with the couplers attached to the ends thereof thereby being at a level offset upwardly with respect to the neutral axis of the sliding center sill. The force of impacts on the couplers, therefore, creates bending stresses in the sliding center sill, such that when severe impacts are occasioned, the latter tends to become damaged, as by buckling.

Accordingly, it is a further object of the invention to provide a railway car of the cushion underframe type, having the neutral axis of the longitudinally extending center portion thereof downwardly offset with respect to the couplers, with the sliding center sill thereof constructed and arranged such that the cushioning device that is interposed between the sliding sill and the car body is employed to cushion impacts applied to the couplers so as to maintain the stresses imparted to the sliding sill by such impacts below a value at which the sill is damaged, as by buckling.

Prior to the invention described in my US. Patent 3,003,436, it was generally accepted that about 10 inches of cushion travel of, for instance, a sliding sill with respect to its underframe in a cushion underframe car under the action of coupler impacts was the maximum that would accomplish any useful cushioning result, and that any length of cushion travel of a practical nature beyond 10 inches would have little effect in reducing lading damage. However, in accordance with the teachings of the aforementioned patent, substantially complete lading protection is obtained when the length of cushion travel is extended to the range of between about 20 inches to 40 inches and the cushion closure characteristics of that patent are employed, with optimum results being achieved at about 30 inches. The cushioning devices that may be employed in practicing the present invention may be of the types described in said patent, and these encompass hydraulic devices, friction devices, rubber devices, pneumatic devices, and combinations thereof arranged as specified in said patent; all of these devices when arranged as specified in said patent will be of the dissipative energy type and will be capable of dissipating and transferring substantially all of the kinetic energy imposed upon the sliding sill by coupler impacts, with the exception of that required to return the device to its initial position after the impact has been cushioned.

The long travel hydraulic cushion device disclosed in said patent can be designed for operating pressures up to the limit of the hydraulic cylinder involved, and such device, when employed in a cushion underframe car as described in said patent, is capable of handling kinetic energy of impact on the order of 1,000,000 ft. lbs., de-

pending upon the specific design for a specific purpose,

considerations of which are the expected speeds of impact, and the masses of cars involved.

longitudinal forces occasioned by impacts at the couplers.

It is still another object taken in conjunction with the immediately foregoing object to provide a sliding center sill and a long travel cushioning device of the type indicated constructed and arranged so that the cushioning device is employed for an increment of the total length of travel of such cushioning device to protect the center sill from damage.

A further object of the invention is to provide a cushion underframe railway car wherein the sliding center sill and long travel cushioning device of the type indicated are constructed and arranged so that the cushioning device serves to reduce damage to the sliding center sill structure upon the application of a buff force at the couplers and at the same time provides protection against lading damage.

It is still another object to provide a cushion underframe railway car with a sliding center sill and a hydraulic long travel cushioning device of the type having a cushion travel in the range of between about 20" to about 40, preferably 30", and having substantially constant force travel closure characteristics constructed and arranged so that such cushioning device serves to reduce the stresses imparted into the sliding sill when an impact is applied on the couplers and, at the same time, provides protection against lading damage.

Another object is to provide a cushion underframe railway car wherein the sliding center sill and cushioning device are constructed and arranged so that the cushioning device serves to reduce the stresses imparted into the sliding sill when an impact is applied on the couplers either in buff or draft.

Generally, the cushioning arrangement for cushion underframe railway cars in accordance with this invention comprises a sliding sill supported for movement lengthwise of the car body and supporting couplers on the remote ends thereof. The sliding sill comprises a plurality of column-like sections which are movable relatively to each other from a neutral position providing a selected sliding sill length to a predetermined position assumed upon application of buff impact resulting in a lesser or contracted sill length and also relatively movable to a predetermined position assumed upon the application of a draft impact, resulting in a greater or extended sliding sill length. The cushioning device is operatively associated with the sill sections and disposed relative thereto so as to provide a cushioning action at least during movement of the sill sections to the contracted position, thereby to reduce stresses imparted through the length of the sliding sill. Means are provided on the car body and sill cooperating with the cushioning device to accommodate the full length of travel thereof, so as to provide lading protection upon both draft and buff impacts to the couplers.

Further objects and features will hereinafter appear.

In the drawings:

FIG. 1 is a perspective view of a railway car of the cushioned underframe type with some of the parts being broken away to show underlying details of structure and employing the cushioning arrangements of the present invention;

FIG. 2 is a fragmentary perspective view of the sliding center sill construction and the cushioning device employed in the cushioning arrangement of the underframe car shown in FIG. 1;

FIG. 3 is an enlarged fragmentary view of the sliding center sill taken in the encircled portion of FIG. 2;

FIG. 4 is a fragmentary cross-sectional view of an end of a column section of the sliding center sill showing the coupler attached thereto;

FIG. 5 is a fragmentary side elevational view of the sliding center sill;

FIG. 6 is a fragmentary cross-sectional view taken substantially along the lines 66 of FIG. 5;

FIG. 7 is a cross-sectional view taken substantially along the lines 7-7 of FIG. 5;

FIG. 8 is a cross-sectional View taken through a cushioning device disposed in the cushion pocket provided in the center sill construction shown in FIG. 2;

FIG. 9 is a fragmentary plan view of a cushioning arrangement showing the relative positions of the sliding center sill components and cushioning device in a neutral position;

FIG. 10 is a fragmentary plan view similar to FIG. 9, but showing the relative positions of the components after an impact has been applied in buff, but prior to the time the cushioning device has completed its full length of travel;

FIG. 11 is a fragmentary plan view similar to FIGS. 9 and 10, but showing the relative positions of the components when the cushioning device has completed its full length of travel;

FIG. 12 is a fragmentary side elevational view of a further embodiment of a cushioning arrangement employing the principles of the present invention; and

FIG. 13 is a fragmentary cross-sectional view taken substantially along the lines 1313 of FIG. 12.

Referring now to the drawings, particularly FIGS. 1-11, there is illustrated one form of the cushioning arrangement 10 of the present invention embodied in a cushioned underframe railway car 11 of which the car body 12 may be a flat car design, as shown in full lines, or may be an enclosed car design, as shown by the phantom lines. The car body 12 includes a cargo or lading-supporting floor 13, from the bottom side of which there depends a stationary center sill 14. Mounted for lengthwise movement in the stationary center sill 14 is a sliding center sill 16 which supports a cushioning device 17, which preferably is of the type described in my said Patent 3,003,436 (and thus may be termed a long travel cushion device) arranged in accordance with the present invention to cooperate with the car body 12 so as to protect the lading carried thereon from damage. The sliding center sill 16 and cushioning device 17 are also constructed and arranged so as to reduce damage to the sill 16 in accordance with the principles of the present invntion when impact is applied to the couplers 18 mounted on each end thereof.

The car may be of the kind having its coupler attached along a line which is vertically displaced with respect to the neutral axis of the longitudinally extending center portion of the car.' As shown, the level of the floor 13 in the car 11 is vertically displaced below the center line C of attachment of the coupler 18 so that the neutral axis n of the sliding center sill 16 is correspondingly displaced. The stationary center sill 14 includes a pair of spaced channels 19 having fixed on the upper horizontal flange the floor structure 13 formed from suitable sheet material of substantial thickness having side sills 21 and end sills Z2 fastened thereto. To provide additional support for the floor 13, there may be provided cross-members and bolsters 23 which extend between the stationary center sill and the side sills in a more-or-1ess conventional manner. The end portions of the car are provided with raised sections 24 which are adapted to receive the coupler housings 26 of the sliding center sill 16.

As heretofore described, the car 11 is formed with a low profile such that the floor 13 is below the level of the center line of the coupler, as required by government regulations standardizing the coupler distance above track level. This structure necessitates that the neutral axis n of the sliding center sill 16 also be located below the level of the coupler. Under such conditions, the sliding center sill 16 supporting the couplers 18 is subject, upon impact at the couplers 18, to forces which create bending moments in the sill 16. For example, at impact speeds of about mph, the coupler force may be on the order of approximately 1,000,000 lbs., depending on the type of cushioning device employed and the masses involved, so that when this force is eccentrically imparted into the sliding center sill 16 through the coupler 18 along the center line C which is offset with respect to the neutral axis n of the sliding center sill 16, the latter is subject to buckling.

In accordance with the present invention, the sliding center sill 16 is constructed such that the stresses imparted thereto through the couplers are materially reduced whereby the buckling forces are minimized. To this end, the sliding sill is formed of sections which are relatively movable to each other so that upon draft the length of the sill between the couplers is extended and upon buff impact, the sill is contracted. As shown, the sliding center sill 16 comprises essentially two columnlike sections 16a and 16b supporting on each end thereof the couplers 18 and including means 27 for interconnecting the sections 16a and 16b for limited movement between an abutting position and a spaced position corresponding to a sill-contracted and sill-extended position, respectively.

As shown in FIGS. 3 to 11, the column-like sections 16a and 16b are each formed of two channel-shaped members 28 of C-section. The channel members 28 are maintained horizontally spaced by an upper plate 31, disposed between the channels and lying flush with the upper horizontal flanges 32 and a lower plate 33, which is arranged to underlie the lower horizontal flanges 34. The remote ends of the sections 16a and 16b are each formed with a suitable coupler housing 26 which, because of the nature of the low profile of the car, extends above the upper horizontal flanges 32 of the column sections.

The sliding center sill, including the sections 16a and. 16b, is slidably disposed in the stationary center sill 14 and may be guided for longitudinal movement therein by suitable guide angles 20. Advantageously, there may also be provided suitable complementary wear strips a fixed to the sliding sill 16 and stationary sill.

The couplers 18 may be of any suitable type such as a tight lock type or a swivel shank coupler type. Advantageously, there is employed in the car structure illustrated a type E coupler of more-or-less conventional construction and which, as shown in FIG. 4 comprises generally a coupler head 36 from which there depends a shank 37 which is received in an openended bushing 40 fixed in the coupler housing 26. An opening 38 in the shank 37 receives a horizontally disposed shank pin 39, of which the ends are disposed in an elongate slot 41 formed in the bushing member 40. With this arrangement the coupler 18 is turnable in a horizontal plane. To prevent the coupler from lashing to and fro in its horizontal plane of turning, there is provided a snubber 42 formed as a resilient pad structure and having exterior metal followers 43 between which there is disposed a plurality of resilient pads 44, such as rubber or the like, separated by metal plates 45. The snubber ,42 is disposed in a pocket defined by the end of the interior bushing 40 and by spaced stops 47 suitably braced by bracing members 48. In operation, the left follower plate 43 engages the shank 37 projecting through the bushing 40 so as to maintain a forward thrust thereon, just sufiicient to prevent lashing of the latter.

The column sections 16a and 16b are connected by tie means 27 which, in the embodiment shown, comprise two pairs of tie plates 48 and 49 of which the tie plates 48 are each rigidly fixed on one end as by welding to the respective sides of the column section 16b and the ends of the tie plates 49 are each rigidly fixed to the respective sides of the other column section 16a. Fixed to the free ends of the tie plates 48 overlying the section 16a is a horizontal cross-member 51 which extends through aligned slots 52 formed in the side walls of the channels 28. The free ends of the tie plates 49 overlying the section 16b are similarly connected by a horizontal cross bar 53 which projects through aligned slots 54.

The tie plates 48 and 49 and the slots 52 and 54 are arranged so as to permit limited movement of the column sections 16a and 16b between an abutting position and a limited spaced position upon a force applied at couplers 18 in buff and draft respectively. In order to protect the sliding center sill 16 from the damage during the application of a coupler force in accordance with the present invention, the long travel cushion device 17 is employed between the sections 16a and 16b. To accommodate the long travel cushion 17, there are provided stop members 55 fixedly secured, as by welding, to the inner sides of each of the channels 28 of the column sections 16a and 16b. Suitable braces 56 may also be provided. The stops 55 on the respective sections 16a and 16b are located so that they abut the respective follower members 57 and 58 of the cushioning device 17 in the fully expanded position thereof as shown in FIG. 9. In this position of the cushion device 17, the cross bars 51 and 53 are aligned with the stop members 55 and also abut the cushion follower members 57 and 58.

In the embodiment shown in FIGS. 1-11, the lengths of the section tie members 48 and 49 and the slots 52 and 54 are proportioned such that the cross bars 51 and 53 are located intermediate the ends of the slots when the car is at a standstill so that the cushioning device is operative to absorb the shock of impact imparted to the sliding center sill at the couplers in both buff and draft as more fully described hereinafter. With this arrangement accommodating both buff and draft forces, it is possible to obtain the most effective use of the cushioning characteristics of the particular cushioning device employed. Assuming that approximately a 10-inch cushion travel is required to adequately cushion coupler forces applied in buff sufiiciently to prevent damage to the sliding center sill 16, the lengths of the slots and the tie members are proportioned such that the 10-inch length of cushion travel is accomplished during movement between the neutral position shown in FIG. 9 and the position in which the adjacent section ends abut, as shown in FIG. 10. In accordance with known principles, the length of cushion travel required to reduce damage causing stresses in the sill during draft is generally maintained less than the length of cushion travel required for the same purpose in buff. In one type of coupler commonly employed, the ratio of draft travel to buff travel is about 2 inches to 3% inches so that if it is desired to retain this relationship with the sliding structure of the present invention, it is a simple matter to calculate the slot lengths and tie plate lengths with respect to the desired contracting movement of the sill sections for cushioning the sill in buff.

The above ratio of the draft to butt travel is merely exemplary of the practice followed heretofore. Should, however, the structural stress characteristics of the sliding sill be such that the ratio may be varied, the proportional lengths of the slots and tie plates may be correspondingly calculated. Under some circumstances, the structural design of the center sill may be such that it is capable of withstanding stresses associated over a full range of coupler forces normally encountered in draft such that the cushioning device may not be required to reduce the energy imparted to the sill to prevent damage thereto. When this condition exists, the slots may be arranged such that the cross bars 51 and 53 engage the end walls of the slots 52 and 54 in a neutral position so that no relative movement occurs between the sill sections 16a and 16b upon the application of a draft force, which, as

above mentioned, imparts stresses of much lesser magnitude than those imparted in butt. However, relative movement of the sections 16a and 16b results upon the application of a butt force.

The long travel cushioning device 17 is supported in the cushioning pocket'60 as shown in FIG. 8 with its follower plates disposed in its expanded position, shown in phantom lines, in abutting relation with the stops 55 and cross members51 and 53. Advantageously, and as already indicated, there may be employed in the present invention as device 17 a hydraulic long travel cushioning device embodying the principles described in said U.S. Patent 3,003,436, which together with my application Serial No. 782,786 disclose a specific form of hydraulic cushion device suitable for use as device 17. Another suitable cushioning device embodying these principles is described in my U.S. patent applications Serial Nos. 146,769 and 146,770, each assigned to the assignee of the present invention.

The cushioning device 17 in the form illustrated includes generally a hydraulic fluid filled cylinder 59 telescopingly arranged with respect to a fluid displacement member 61. The fluid displacement member 61 includes a hollow piston rod 62 having connected to one end the follower plate or closure plate 58 and on its other end an axially orificed piston head 63 slidable within the cylinder 59 so as to define a high pressure chamber 64 between the follower or closure member 57 on one end of the cylinder and a low pressure chamber 65 on the other side thereof. Located in the low pressure chamber 65 and intermediate the ends of the cylinder is a cylinder head 66 having an axial bore 67 through which the piston rod 62 extends. An invaginating tube 68 is connected to the cylinder head 66 and at its other end to the piston rod. The invaginating tube 68 serves to provide a receptacle for receiving the hydraulic fluid displaced from the high pressure chamber 64 to the low pressure chamber 65 via an annular opening 69. The rate of flow of the hydraulic fluid from the low pressure chamber 64 through the piston orifice 71 upon relative displacement of the cylinder 59 and piston 61 is controlled by an orifice pin 72 fixed to the closure member 57 and extending through the orifice 71.

Preferably, the orifice pin 71 is constructed so as to provide approximately constant force travel closure characteristics in the cushioning device and to this end, in the embodiment illustrated the pin is provided with flutes 73 of varying lengthwise depth so that for substantially each increment of relative travel of the fluid displacement means 61 and the cylinder 59, a substantially constant resisting force is provided by the cushioning device. For returning the cylinder 59 and fluid displacement means 61 to their original expanded position, there is provided between the closure plates 57 and 58 a compression spring 74.

As more fully described in the aforementioned patent, the long travel cushioning device is constructed so as to provide a travel in the range of between about 20 to about 40 inches of cushion travel in either direction, preferably 30 inches. The above-described cushioning device is operative upon impact in bufi or draft to contract so that the piston head 63 is operative to displace fluid from the high-pressure chamber 64 to the low-pressure chamber 65 via. the piston orifice 71 at a rate controlled by the metering pin 72 and through the hollow piston rod 68 via openings 76 provided therein. Upon entry of the fluid into the low-pressure chamber 65, the turbulence created thereby dissipates a portion of the energy of an impact in the form of heat. Liquid in the low pressure chamber also flows via the annular passage 69 into the invaginating tube 68. Thus, the device dissipates and transfers during its full length travel substantially all the kinetic energy imposed upon the sliding sill by draft and butt forces applied to the car couplers with the exception of that stored inthe spring 74 which serves, after the force of impact has dissipated,to return the device to its fully extended position.

With the cushion device of the type illustrated, the full length of travel of the cushioning device 17 is employed to obtain the benefits of the principles disclosed in said Patent 3,003,436. To this end, cushion keys 77 are provided on the car body 12 and spaced so that the total movement of the sill relative to the car body permits the device to travel its full length of travel in either direction from its normal position say, for example, 30 inches. As shown, the cushion keys 77 are fixed in spaced pairs to the floor 13 and the lower plate of the stationary sill 14 so as to extend into the stationary sill enclosure 78 and be engageable with the closure members 57 and 58 above and below the respective cross bars 51 and 53.

As shown in FIG. 9 in the neutral position of the car 11, the cushioning device '17 is in its fully expanded position with the closure members 57 and 58 engaging the car body cushion keys 77. In this position under the influence of the cushion spring'74, the column sections 16a and 1617 are maintained in spaced relationship with the cross bars 51 and 53 associated with the respective tie bars 48 and 49 abutting the closure paltes 57 and 58 disposed between the ends of the slots 52 and 54. In the neutral position the stop members 55 also engage the closure plates. As explained heretofore, upon the application of impact at the coupler in buff or draft, the column sections are movable relative to each other so that the cushioning device is employed to absorb a portion of the energy of impact before the sections moving to a limit position as determined by the proportionate length of the slots 52 and 54 and the tie plates 48 and 49.

Assuming a force F in buff at the coupler, as shown in FIG. 10, relative movement of the column sections 16a and 16b occurs whereby the force F causes the column section 16b to move to the right in respect of the substantially stationary column section until the column sections 16a and 16b abut and the cross bars 51 and 53 contact the ends of the respective slots 52 and 54. As shown, the cross bar 53 carried by the stationary column section 16a by way of tie plates 49 remains substantially stationary and the section 16b moves relative thereto until it contacts the left end of slot 54. The cross bar 51 moves 'with the column section 1612 until it abuts the right end of the slot. In these respective positions, the cross bars 51 and 53 are moved out of contact with the closure mem bers 57 and-58. However, the stop members 55 and closure members 57 and 58 carried by the movable and substantially stationary column sections 16a and 16b serve to compress the cushion device 17 so that the latter resists the force of impact during the travel to the abutting or bufi position of the column sections. In this manner, a portion of the impact of the force at the coupler is absorbed by the cushioning device during the movement of the column sections to an abutting or bufi'f position so that the absorbed energy is not imparted through the total length of the two column sections of the sill, thereby to reduce the stresses imparted therein.

During the period in which the column sections 16a and 16b move to an abutting position, little, if any, relative movement occurs between the sliding center sill and the car body. However, the cushioning device has not completed its full length of travel such that sections 16a and sections 16]) move conjointly and the sliding center sill 16 moves as a unit relative to the car body and the .stop members 55 on the section 161; continue to contact the closure plate 58 and depress the cushion against the cushion keys 77 fixed on the car body; the stop members 55 being spaced from the closure member 57. In this manner, the cushioning device is operative during its full length of travel to absorb energy by dissipation and transfer at a magnitude sufficient to protect the lading carried by the car body from damage, in accordance with the principle-s of U.S. Patent 3,003,436.

From the foregoing, it is readily'apparent that when 9. the sliding center sill sections 16a and 16b are subect to buff, the stop lugs 55 on the sliding center sill 16 serve to compress the cushion. However, when the sill 16 is subject to a draft force, the cross bars 51 and'53 serve to compress the cushioning device 17. Assuming a force in draft at the left end of the sliding center sill 16, the section 16b moves relative to the substantially stationary column section 16:: until the right end of the slots 54 abut the cross bar 53 supported by the tie plates 49 connected to the stationary sliding sill section 16a. At the same time, the cross bar 51 carried by the tie plates 48 which are fixed to the moving sliding sill section 16b moves forwardly in the slots 52 until contact is made with the left end thereof. Thus, the cross bar 53 remains substantially stationary and in contact with the closure member 58 of the cushioning device 17 and the cross bar 51 moves so as to compress the cushion against the substantially stationary cross bar 53. In this manner, the length of relative travel of the cross bars 51 and 53 reflecting the relative movement of the column sections 16a and 16b serve to compress the cushioning device so that the latter is operative to cushion the draft force applied at the couplers 18 during the movement of the sill sections to the draft position thereof. As heretofore described in connection with the buff position, upon reaching the draft position the sections move conjointly so that the sliding sill moves as a unit for the remainder of the length of travel of the cushioning device, thereby to absorb further energy of the impact and reduce the damage to the lading carried on the car body.

With the cushioning device embodying the principles of US. Patent 3,003,436 wherein a length of travel of about 30 inches is employed, particularly unique results are obtained with the cushioning arrangement described herein. With this arrangement, upon the application of a typically severe impact of rn.p.h. a force is applied to the coupler and approximately 150,000 ft. lbs. of energy may be dissipated in the exemplary 10-inch travel of the column sections in the presence of a buff force. Moreover, the cushioning device during its full length of travel achieves the unique results in protecting the lading from damage as described in the aforementioned US. Patent 3,003,436.

However, as heretofore mentioned, the present invention is in no way restricted for use with a cushioning device arranged to provide the principles of the aforesaid patent. Any suitable cushioning device may be employed in connection with the improved sliding sill structure comprising my present invention, though such cushion should be of the dissipative energy system and have sufficient closure travel so that during the period in which the column sections of the sliding center sill move to their limit position, longitudinal shocks acting on the sliding sill, either in buff or draft, are sufliciently cushioned to protect the sill and at the same time some protection against lading damage is offered.

Referring now to FIGS. 12 and 13, there is illustrated another form of the present invention. As heretofore discussed, the coupler forces in buff are generally of greater magnitude than those encountered in draft. Under this set of conditions, it may not be necessary to employ a long travel cushioning device to cushion coupler draft forces. The embodiment illustrated in FIGS. 12 and 13 is particularly adapted for such conditions and the cushioning arrangement is such that the sliding sill structure incorporates means for cushioning the draft forces imparted to the sill at the couplers and the long travel cushioning device is employed to cushion the buff forces.

As shown, the sliding sill 116 is formed with two column-like sections 116a and 116b similarly constructed to the embodiment shown in FIGS. 1-11 and includes spaced channel members 128 which may be held horizontally spaced by suitable plate or bracing members (not shown). The sliding center sill 116 is guided within the stationary center sill 14 depending from the car body 12 by way of guides 20. Wear plates 20a may be complementarily positioned on the sliding center sill 116 and the stationary center sill 14.

The column sections 116a and 116b are interconnected by tie means including means for cushioning the force of impact applied in draft. To this end there is fixed as by welding on each side of the angles 128 of each of the column sections 116a and 116b, a pair of spaced guide blocks 130 and 131 of which the guide blocks 130 are fixed to the abuttable ends of the sections 116a and 116b. Suitable bracing 135 is provided between each pair of blocks 130 and 131. Adhered to the forward face of the guide blocks 130 to prevent metal-to-metal contact upon the application of a buffing force are resilient pads 132, such as rubber or the like. Resilient pad means 133 are adhere along one face to the coupler side of the guide blocks 131 and on the other face to a follower plate 134. Extending through vertically spaced openings 136 extending through the respective guide assemblies including the guide blocks 130 and 131 are tie rods 137 having heads abutting the follower plate 134 on the column section 116b and nuts 138 threadably fastened on the opposite ends of the rods abutting the follower assembly on the column section 116a.

A cushion device 17 is disposed in a cushion pocket formed in the sill 116 including stop members 139 disposed on the inner sides of the channels 128 of each of the column sections 116:: and 116b. The stops 139 are located on the column sections 116a and 116b such that the cushioning device 17 in its expanded position as shown is in contact therewith through follower members 55 and 57 on the opposing ends thereof. In this expanded position, as more fully to be explained hereinafter, a butt force at either end of the sliding center sill 116 is absorbed by the cushioning device 17.

As shown, the lengths of the tie rods 137 are such that the total length of travel from the neutral spaced position of the sections 116a and 116b, illustrated in FIG. 12, to an abutting position, is less than the length of travel of the cushioning device 17. To achieve the lading protection benefits resulting from the full length of travel of the cushioning device there is fixed to the underside of the floor 13 and to the base plate of the stationary center sill 14 a pair of,vertically disposed and lengthwise spaced key members 141 located so as to be aligned with the stop members 139 in the neutral position of the sliding center sill 116. Hence in the neutral position of the sliding center sill, the key members 141 also contact the follower plates 55 and 57 on the opposite ends of the cushioning device.

The cushioning device 17 employed may be of the type embodying the principles of the aforementioned Patent 3,003,436 and hereinbefore generally described.

In operation, assuming a buff force F in the direction shown in FIG. 12, the column sections 11611 and 116a move relative to each other with the tie rods 137 sliding through the guide block openings 136 until the pads 132 abut. During this period of travel, the stop members 139 carried on each of the column sections 116a and 116b contract the cushion so that energy dissipating characteristics of the cushioning device 17 is employed to thereby reduce the energy imparted into the length of the sliding center sill 116 comprising the two column sections 116a and 116b in a manner heretofore described in connection with the embodiment of FIGS. 1-11.

During the period in which the sections move to an abutting or buff position, there is substantially no relative movement between the column section 116a and the car body 12. The key members 141 on section 116a remain in contact with the follower 57, and the key members 141 on section 116b are displaced out of contact with the opposite follower 58 under the influence of the force which causes the section 116b to move to the right relative to the stationary car body.

After the sections 116a and 116b abut, the cushioning device 17 continues to contract for its full length of travel, and the stop members 139 on the section 116b continue to compress the cushion in the direction of the force F against the stop and key members 139 and 141 on the section 116a and car body 12 so that the sliding sill moves relative to the car body 12 as a unit. In this manner, the lading protection benefits made available by using the cushioning device 17 are achieved.

When kinetic energy associated with the buff impact has been fully dissipated and transferred, the spring 65 serves to return the sill sections 116a and 116!) to the neutral position shown.

Assuming a draft force applied on the sliding sill section 116b, the latter section tends to move to the left relative to the substantially stationary sliding sill section 116a. The tie rods 137 resist this movement by way of the head 138 and nut ends 134 thereof contacting the follower plates 134 which compress the cushion pads 133. In this manner, the cushion pads 133 absorb a portion of the impact applied in draft. It is, of course, to be understood that in the event the single pads 133 are inadequate, a plurality of such pads may be employed.

As described above in connection with the buff impact at the couplers, upon reaching the draft position wherein the sill is fully extended the sections 116a and 116b are movable conjointly and the sliding sill moves as a unit for the remainder of the travel of the cushioning device. In this manner, the energy-absorbing characteristics of the cushioning device are employed to provide the lading protection.

What is'claimed is:

1. A cushioned railway vehicle comprising a car body including a sliding si-ll structure slidably supported by said car body, coupler means mounted on the remote ends of said sliding sill structure, said sliding sill structure including two endwise positioned sections, means interconnecting said sections for movement relative to one another from a spaced neutral position in the absence of a buff force on the coupler means toward each other to a position in which said sections are conjointly movable upon application of a buif force to said coupler means, said sections being movable relative to said car body at least when in said conjointly movable position, a cushion pocket defined by first stop means forming a part of each of said sections, a cushioning device having a total travel greater than the travel of said sections to said conjointly movable position disposed in said pocket between said first stop means and being operative upon the application of a buff force applied to said coupler means when said sliding sill structure is in a neutral position to resist relative movement of said sections from said neutral position, thereby to dissipate a portion of the energy of the buif force during the movement of said sections to said conjointly movable position so as to prevent damage to said sliding sill structure, and second stop means carried by said car body and engaging said cushioning device, said cushioning device being operative during the full length of travel thereof to provide relative movement between said sliding sill structure and said car body so as to prevent substantial damage to the lading carried by said vehicle.

2. In a railway vehicle having an underframe and having mounted thereon a longitudinal sliding sill structure supporting couplers on the remote ends thereof and interconnected with said underframe through cushioning means of predetermined total closure distance for controlled relative movement between said sill structure and underframe in response to buff and draft forces applied to said couplers to an extent equal to said predetermined total closure to protect said underframe, the improvement comprising said sill structure being formed from normally separated longitudinal sill sections each operatively engaged with said cushioning means to close said cushioning means during movement of a sill section longitudinally of said underframe upon buff and draft force application to said couplers to provide protection to said underframe continuously throughout the distance of total closure of said cushioning means, the distance of total closure of said cushioning means being greater than the distance of normal separation of said sill sections, and means interengaging said sill sections independently of said cushioning means, which means under all conditions of buff and draft force application to said couplers provide at least substantially rigid interconnection between said sill sections for conjoint movement thereof longitudinally of said underframe, said interengaging means at least under all conditions of buff force application to said couplers further providing for initial limited movement of at least one sill section toward another relative to said underframe during which initial limited movement at least initial partial closure of said cushioning means occurs whereby both said sill structure and underframe are protected throughout the distance of initial partial closure of said cushioning means.

3. A railway car comprising a body portion supporting a longitudinal sill structure projecting at opposite ends of said body portion and carrying coupler means thereon, means mounting said sill structure for movement relative to said body portion longitudinally thereof, said sill structure being divided into a pair of independently and simultaneously movable sill sections which in the neutral position of said sill structure include longitudinally spaced inner end portions, the outer end portions of said sill sections carrying said coupler means, a longitudinally compressible cushion unit aligned with said sill sections and extending longitudinally thereof and operatively compressible'between said sill sections upon closing movement of said sill sections toward inner end portion abutment, said cushion unit further being operatively compressible between said sill structure and .body portion longitudinally of said body portion, said cushion unit including opposite end force application means to receive operational force to close said unit, each sill section including means which are longitudinally spaced from one another and are movable with said sill sections and are arranged for opposite end engagement with said force application means of said cushion'unit to provide for at least partial closure of said cushion unit in response to buff impact forces applied at either and both of said coupler means and in response to draft forces applied to one and either of said coupler means, each sill section including further means movable relative toone another but mutually interconnected to permit limited longitudinal separation of said sill sections in response to draft forces applied to said coupler means, and longitudinally spaced means fixed relative to said body portion and arranged for opposite end engagement with said force application means of said cushion unit to provide controlled force transmission to said body portion through said cushion unit during closure thereof, the total closure of said cushion unit being substantially greater than the longitudinal distance of separation and closure be tween said inner end portions of said sill sections, whereby during initial closure of said cushion unit in response to said buff and draft forces applied to said coupler means there is a resulting movement of said si-ll sections relative to one another with said resulting movement being cushioned by said cushion unit, and whereby said body portion is cushioned during anyisubsequent longitudinal movement of the sill structure relative to said body portion throughicontinuing closure of saidcushion unit.

4. In a railway car having an underframe in which a sill structure is mounted for longitudinal movement relative to said underframe, said sill structure projecting substantially beyond opposite ends of said underframe and carrying coupler means on the projecting ends thereof, and movement between said sill structure and underframe being controlled and limited by a single energy transferring and dissipative means of predetermined total capacity interconnecting said sill structure and underframe, the improvement comprising said sill structure being sub-divided into a pair of sill sections, said sill sectons being spaced from one another in the neutral position of said sill structure and underframe-and mova'ble toward one another into energy transferring interrelation at least in response to buff force application to said coupler means for subsequent conjoint movement relative to said underframe, means interconnecting each of said sill sections with said energy transferring and dissipative means to utilize at least a portion of the total capacity thereof to reduce forces of impact applied to one sill section and transferred thereby to the other sill section at least upon buff force application to said coupler means, means interconnecting said underframe with said energy transferring and dissipative means to utilize the total capacity thereof which is available in response to variable conditions of buff and draft force application to said coupler means to reduce the magnitude of forces of impact transferred from said sill structure to said underframe during both relative and conjoint movement of said sill sections relative to one another and to said underframe, and means at least substantially rigidly interconnecting said sill sections for conjoint movement thereof upon draft force application to said coupler means.

5. The railway car of claim 4 wherein said energy transferring and dissipative means is a longitudinally contractible and expansible member having a total stroke which is substantially in excess of 5 inches.

6. The railway car of claim 4 wherein said energy transferring and dissipative means is a longitudinally cont actible and expansible member having a total stroke which is substantially in excess of 5 inches, said coupler means being fixed to said sill sections without secondary limited cushioning therebetween.

7. A cushioned underframe railway vehicle comprising a car body including a stationary center sill, a sliding center sill slidably supported in said stationary sill, coupler means mounted on the remote ends of said sliding sill, said sliding center sill including two endwise positioned column sections, means connecting said sections for relative movement to each other from spaced neutral position in the absence of a buff force on the couplers to an abutting position upon application of a buff force to said couplers, a cushion pocket defined by stop means fixed to the adjacent ends of said sections, a cushioning device having a total travel greater than the travel of said column sections to said abutting position disposed in said pocket between said stop means and being operative upon the application of a buff force applied on said couplers when said sliding sill is in a neutral position to resist relative movement of said column sections from said neutral position, thereby to dissipate a portion of the energy of the buff force during the movement of the column sections to said abutting position so as to prevent damage to said sliding center sill, and lug means carried by said car body and engaging said cushioning device, said cushioning device being operative during the full length of travel thereof to provide relative movement between said sliding center sill and said car body so as to prevent substantial damage to the lading carried by said vehicle.

8. The invention as defined in claim 7 in which said cushioning device comprises a hydraulic cushion having a travel of about 30 inches in either direction of said neutral position.

9. The invention as defined in claim 7 in which said cushioning device comprises a hydraulic cushion having a travel of from about 20 to 40 inches in either direction of said neutral position.

' 10. A railway car comprising a body portion supporting a longitudinal sill structure projecting at opposite ends of said body portion and carrying coupler means thereon, means mounting said sill structure for movement relative to said body portion longitudinally thereof, said sill structure being divided into a pair of independently and simultaneously movable sill sections which in the neutral position of said sill structure include longitudinally spaced inner end portions, the outer end portions of said sill sections carrying said coupler means, a single longitudinally compressible cushion unit aligned with said sill sections and extending longitudinally thereof and operatively compressible between said sill sections upon movement of said sill sections toward inner end portion abutment under all conditions of buff impact force application at either and both ends of said sill structure, said cushion unit further being operatively compressible between said sill structure and body portion longitudinally of said body portion solely in the direction of buff impact force application at one and either end of said sill structure, said cushion unit including opposite end force application means to receive operational force to close said unit, said sill sections including portions which are mutually telescopic, each sill section including means longitudinally spaced and movable therewith and arranged for opposite end engagement with said force application means of said cushion unit to provide for closure of said cushion unit in response to buff impact forces applied at either and both of said coupler means and in response to draft forces applied to one and either of said coupler means, and longitudinally spaced means fixed relative to said body portion and arranged for opposite end engagement with said force application means of said cushion unit to provide controlled force transmission to said body portion through said cushion unit during closure thereof, the total closuer of said cushion unit being substantially greater than the longitudinal distance between said inner end portions of said sill sections, whereby there is initial closure of said cushion unit in response to buff impact forces applied to either of said coupler means resulting in movement of said sill sections at least toward inner end portion abutment with said sill sections being cushioned by said cushion unit, and whereby said body portion is also cushioned during closure of said sill sections provided that said buif forces cause at least some subsequent longitudinal movement of the closed sill structure relative to said body portion, said body portion being further cushioned by continuing closure of said cushion unit which accompanies continuing relative movement of the closed sill structure.

11. A railway car comprising a body portion support ing a longitudinal sill structure projecting at opposite ends of said body portion and carrying coupler means thereon, means mounting said sill structure for movement relative to said body portion longitudinally thereof,-said sill tructure being divided into a pair of independently and simultaneously movable sill sections which in the neutral position of said sill structure'include longitudinally spaced inner end portions, the outer end portions of said sill sections carrying said coupler means, a longitudinally compressible cushion unit aligned with said sill sections and extending longitudinally thereof and operatively compressible between said sill sect-ions upon closing movement of said sill sections toward inner end portion abutment, said cushion unit further being operatively compressible between said sill structure and body portion longitudinally of said body portion, said cushion unit including opposite end force application means to receive operational force to close said unit, said sill sections including portions which are mutually telescopic, each sill section including means longitudinally spaced and movable therewith and arranged for opposite end engagement with said force application means of said cushion unit to provide for at least partial closure of said cushion unit in response to buff impact forces applied at either and both of said coupler means and in response to draft forces applied to one and either of said coupler means, each sill section including further means movable relative to one another but mutually interconnected to permit limited longitudinal separation of said sill sections in response to draft forces applied to said coupler means, and longitudinally spaced means fixed relative to said body portion and arranged for opposite end engagement with said force application means of said cushion unit to provide controlled force transmission to said body portion through said cushion unit during closure thereof, the total closure of said cushion unit being substantially greater than the longitudinal distance of separation and closure between said inner end portions of said sill sections, Whereby during initial closure of said cushion unit in response to said bulfand draft forces applied to said coupler means there is a resulting movement of said sill sections relative to one another with said resulting movement being cushioned by said cushion unit, and whereby said body portion is cushioned during any subsequent longitudinal movement of the sill structure relative to said body portion through continuing closure of said cushion unit.

12. A railway car comprising a body portion supporting a longitudinal sill structure projecting at opposite ends of said body portion and carrying coupler means thereon, means mounting said sill structure for movement relative to said body portion longitudinally thereof, said sill structure being divided into a pair of independently and simultaneously movable sill sections which in the neutral position of said sill structure include longitudinally spaced inner end abutment portions, the outer end portions of said sill sections carrying said coupler means, a single longitudinally contractible cushion assembly aligned with said sill sections and operatively contractible during movement between said sill sections and between said sill structure and body portion longitudinally of said body portion, means carried by said sill sections engaging opposite ends of saidcushion assembly to provide for total closure of said cushion assembly in response to substantial buff and draft forces applied to'said coupler means, further means carried by said sill sections movable relative to one anotherbut arranged for mutual interconnection to permit limited longitudinal separation of said sill sections in response to draft forces applied to one and either of said coupler means, and means fixed relative to said body portion and arrangedfor opposite end engagement with said cushion assembly to provide controlled buff and draft force transmission to said body portion through said cushion assembly during total closure thereof, said further means and the engagement ofsaid sill sections and bodyportion with said cushion assembly being arranged to provide for at least partial contraction of said cushion assembly during movement of said sill sections into limited longitudinal separation, the total closure of said cushion assembly being substantially greater than the longitudinal distance between said inner end portions of said sill sections in the neutral and separated positions thereof.

13. The railway car of claim 12 wherein said sill sections are in the form of basically hollow columns with said cushion assembly being received Within at least one of said sill sections and with said means engaging said cushion assembly being arranged for balanced force application to said cushion assembly at opposite ends thereof while being independent of one another at said opposite ends.

14. A railway car comprising a body portion supporting a longitudinal sill structure projecting at opposite ends of said body portion and carrying coupler means thereon, means mounting said sill structure for movement relative to said body portion longitudinally thereof, said sill structure being divided into a'pair of independently and simultaneously movable sill sections which in the neutral position of said sill structure include longitudinally spaced inner end portions, the outer end portions of said sill sections carrying said coupler means, a single longitudinally compressible cushion unit aligned with said sill sections and extending longitudinally thereof and operatively compressible and expansible therebetween and between said sill structure and body portion longitudinally of said body portion, said I cushion ;unit including opposite end force application means to receive operational force to close said unit, said sill sections including portions which are mutually telescopic, each sill section including means longitudinally spaced and movable therewith and arranged for opposite end engagement with said force application means of said cushion unit to provide for at least partial closure'of said cushion unit in response tobulf and draft forces applied to said coupler means under all conditions of operation of said car, and longitudinally spaced means fixed relative to said body portion and arranged for opposite end engagement with said force application means of said cushion unit to provide controlled force application to, said body portion through said cushion unit during closure thereof, the total closure of said cushion unit being substantiallygreater than the longitudinal distance between said inner end portions of said sill sections with said cushion unit overextending said longitudinal distance, whereby during initial closure of said cushion unit in response to buff and draft forces applied to either or both of said coupler means the resulting movement of said sill sections is cushioned by said cushion unit and said body portion is cushioned during any subsequent longitudinal movement of said sill structure relative to said body portion through continuing closure of said cushion unit.

15. A sliding center sill for a railway vehicle comprising two endwise positioned and spaced column sections, means on the remote ends of each of said column sections for attaching couplers thereto,.means interconnecting said sections for limited movement between an abutting position at adjacent ends resulting from a buff force applied on said couplers and to spaced position at adjacent ends resulting from a draft'force applied on said couplers, said interconnecting means including a first pair of tie plates attached to one of said column sections and overlying said other column section and including a cross member fixed for movement with said first pair of plates and extending through slots provided in said other column section, a second pair of plates fixed to said other column section and overlying said one column section and including a cross member fixed for movement wtih said other pair of plates and extending through slots provided in said one column section, and cushioning means confined between said cross membersand separately engaged by said column sections at opposite ends thereof.

16. A railway car comprising a body portion supporting a longitudinal sill structure projecting at opposite ends of said body portion and carrying coupler means thereon, means mounting said sill structure for movement relative to said body portion longitudinally thereof, said sill structure being divided into a pair of independently and simultaneously movable sill sections which in the neutral position of said sill structure include longitudinally spaced inner end portions, the outer end portions of said sill sections carrying said coupler means, a longitudinally contractible cushion unit aligned with said sill sections and extending longitudinally thereof and operatively contractible and expansible therebetween and between said sill structure and body portion longitudinally of said body portion, said cushion unit including opposite end force application means to receive operational force to close said unit, said sill sections including portions which are mutually telescopic, each sill section including means longitudinally spaced and movable therewith and arranged for opposite end engagement with said force application means of said cushion unit to provide for at least partial closure of said cushion unit in response to bufi and draft forces applied to said coupler means, and longitudinally spaced means fixed relative to said body portion and arranged for opposite end engagement with said force application means of said cushion unit to provide controlled force application to said body portion through said cushion unit during closure thereof, the total closure of said cushion unit being substantially greater than the longitudinal distance between said inner end portions of said sill sections, whereby in response to forces applied to said coupler means any resulting movement of at least one of said sill sections toward inner end portion abutment with the other is cushioned by initial closure of said cushion unit and said body portion is cushioned during any subsequent longitudinal movement of said sill structure relative to said body portion through continuing closure of said cushion unit.

17. A railway car comprising a body portion supporting a longitudinal sill structure projecting at opposite ends of said body portion and carrying coupler means thereon, means mounting said sill structure for movement relative to said body portion longitudinally thereof, said sill structure being divided into a pair of independently and simultaneously movable sill sections which in the neutral position of said sill structure include longitudinally spaced inner end portions, the outer end portions of said sill sections carrying said coupler means, a single longitudinally contractible cushion unit aligned with said sill sections and extending longitudinally thereof and operatively contractible and expansible therebetween and between said sill structure and body portion longitudinally of said body portion under all conditions of buff impact force application at either end of said sill structure and solely in the direction of buff impact force application at one and either end of said sill structure, said cushion unit including opposite end force application means to receive operational force to close said unit, said sill sections including portions which are mutually telescopic, each sill section including means longitudinally spaced and movable therewith and arranged for opposite end engagement with said force application means of said cushion unit to provide for at least partial closure of said cushion unit in response to buif impact forces applied at either and both of said coupler means and in response to draft forces applied to one and either of said coupler means, each sill section including further means movable relative to one another but mutually interconnected to permit limited longitudinal separation of said sill sections in response to draft forces applied to said coupler means, and longitudinally spaced means fixed relative to said body portion and arranged for opposite end engagement with said force application means of said cushion unit to provide controlled force application to said body portion through said cushion unit during closure thereof, the total closure of said cushion unit being substantially greater than the longitudinal distance of separation and closure between said inner end portions of said sill sections, whereby in response to forces applied to said coupler means any resulting movement of at least one of said sill sections toward inner end portion abutment with the other is cushioned by initial closure of said cushion unit and said body portion is cushioned during any subsequent longitudinal movement of said sill structure relative to said body portion through continuing closure of said cushion unit.

References Cited by the Examiner UNITED STATES PATENTS 1,124,952 l/1915 Richey 213-8 1,947,316 2/1934 Suckow 2138 1,997,170 4/1935 Egen 2138 2,022,253 11/1935 Nortz 2138 2,043,344 6/1936 Alma et al 2l38 2,973,102 2/ 1961 Nystrom 2138 FOREIGN PATENTS 1,175,883 11/1958 France.

MILTON BUCHLER, Primary Examiner.

LEO QUACKENBUSH, Examiner. 

1. A CUSHIONED RAILWAY VEHICLE COMPRISING A CAR BODY INCLUDING A SLIDING SILL STRUCTURE SLIDABLY SUPPORTED BY SAID CAR BODY, COUPLER MEANS MOUNTED ON THE REMOTE ENDS OF SAID SLIDING SILL STRUCTURE, SAID SLIDING SILL STRUCTURE INCLUDING TWO ENDWISE POSITIONED SECTIONS, MEANS INTERCONNECTING SAID SECTIONS FOR MOVEMENT RELATIVE TO ONE ANOTHER FROM A SPACED NEUTRAL POSITION IN THE ABSENCE OF A BUFF FORCE ON THE COUPLER MEANS TOWARD EACH OTHER TO A POSITION IN WHICH SAID SECTIONS ARE CONJOINTLIY MOVABLE UPON APPLICATION OF A BUFF FORCE TO SAID COUPLER MEANS, SAID SECTIONS BEING MOVABLE RELATIVE TO SAID CAR BODY AT LEAST WHEN IN SAID CONJOINTLY MOVABLE POSITION, A CUSHION POCKET DEFINED BY FIRST STOP MEANS FORMING A PART OF EACH OF SAID SECTIONS, A CUSHIONING DEVICE HAVING A TOTAL TRAVEL GREATER THAN THE TRAVEL OF SAID SECTIONS TO SAID CONJOINTLY MOVABLE POSITION DISPOSED IN SAID POCKET BETWEEN SAID FIRST STOP MEANS AND BEING OPERATIVE UPON THE APPLICATION OF A BUFF FORCE APPLIED TO SAID COUPLER MEANS WHEN SAID SLIDING SILL STRUCTURE IS IN A NEUTRAL POSITION TO RESIST RELATIVE MOVEMENT OF SAID SECTIONS FROM SAID NEUTRAL POSITION, THEREBY TO DISSIPATE A PORTION OF THE ENERGY OF THE BUFF FORCE DURING THE MOVEMENT OF SAID SECTIONS TO SAID CONJOINTLY MOVABLE POSITION SO AS TO PREVENT DAMAGE TO SAID SLIDING SILL STRUCTURE, AND SECOND STOP MEANS CARRIED BY SAID CAR BODY AND ENGAGING SAID CUSHIONING DEVICE, SAID CUSHIONING DEVICE BEING OPERATIVE DURING THE FULL LENGTH OF TRAVEL THEREOF TO PROVIDE RELATIVE MOVEMENT BETWEEN SAID SLIDING SILL STRUCTURE AND SAID CARBODY SO AS TO PREVENT SUBSTANTIAL DAMAGE TO THE LADING CARRIED BY SAID VEHICLE. 